Farming of crops of hay has changed radically in the last 3 decades away from permanent storage facilities or fully exposed bales. Currently, cut hay is predominantly rolled in to large cylindrical bales whose diameter is greater than their height. These cylindrical bales are very tightly rolled and are bound into the final shape so as to exclude air and water and to provide for ready movement with large scale equipment as the finished bales can weigh more than 1 ton and be valued at as much as $250 in some regions, each.
To provide for centralized storage and natural curing, the bales are arranged axially, more or less, along the surface of the ground into a laterally arranged tubular array while being simultaneously wrapped in 1 or more layers of plastic film. Automatic machinery is known in the art for this purpose which are adapted to receive individual bales sequentially, and then to compress each new bale on to the end of the axial array of bales and then to wrap the array continuously by rotating supplies of plastic film. Once wrapped the axial array of bales is lowered axially and vertically on to the receiving surface without breaking the seal of the film or the film itself.
As the bale array is advanced the film supply is spirally wound around the main axis in 1 or more individual layers each of which will overlap at least 1 of layer from the previous wrap.
Problematic situations occur when the ground is not level and at the beginning and end of each tubular array. When such situations occur additional wraps my be included by slowing down or stopping the advance of the baler whereby the pitch of spiral may be reduced even to 0 thereby wrapping the bale array in a multi-layer cylindrical fashion.
Even more problematic are the 1st and last bales in an array as the whole array must be kept completely sealed from weather so as to process correctly without losses. Thus, the 1st and last bales are fitted with an end cap which is fed through the wrapper to start or finish an in line array. Wrapping the last bale is problematic as the sheet film must not only overwrap the helix but also must permanently seal the end of the array by extending upstream of the array enough to stretch and seal with the end cap across at least a portion of its final transverse surface.
Such wrapping machines should be operated with great care and patience as the loads and stresses are very high and the moving parts include steel structures which operate rotationally in the open at high relative speeds. Farming efficiency and the vagaries of the weather dictate that wrapping should proceed not only carefully and uniformly but at high and continuous rates of production. Typical farming operations such as this one are conducted on long work shifts often in inclement conditions. Operators must be fully trained and operate strictly in accordance with planned procedures.
All of the rotating parts of the bale wrapper are separated from operator work space by substantial guards which must remain in place before the wrapper severance of the film is required at the trailing end of any bale line. Known machines have left severance of the film and associated termination activities to the user as a manual operation. This involves full stoppage of the wrapper, isolation of hydraulic circuits, removal of machinery guards, manual tearing of the film well inside the outer boundary of the rotating parts and return of the guards. On occasion, operators have been known to ignore machinery guards to reach inside the outer boundary, an entirely unsafe procedure with catastrophic consequences in the event of unplanned actions. This is particularly so where more than 1 layer of film is being applied from 2 or more rotary supply stations where stoppage and severance of the film must procedure in 2 or as many as 4 individual steps.
In more detail, manual severance requires:                (a) stopping the machine feed at the end of supply while still within the cylindrical boundary of the film supply,        (b) this stops machine travel and, thus, the continuous double helix of the wrapping material,        (c) rotary film travel is stopped,        (d) the operator then attends the film area of the machine,        (e) the film area guard is slid laterally to expose the film supply and completely cover the operational controls,        (f) the film is manually torn or cut starting at the downstream side and working across the surface of the film in a generally upstream direction,        (g) the film area guard is slid laterally to its original condition,        (h) the rotary film travel is re-started for 1-2 cycles, and        (i) these steps are repeated.        